Maple Tuna Olive Toastie

Details

Ingredients

• 2 tablespoons butter
• ½ large sweet red onion, thinly sliced
• 1 tablespoon maple syrup
• 2 (5 ounce) cans tuna, drained
• 2 tablespoons creamy salad dressing (such as Miracle Whip®)
• salt and ground black pepper to taste
• 1 (12 ounce) loaf Italian olive bread
• 8 ounces shredded Cheddar cheese